Increasing the flexibility with which an optical transport network can route wavelength channels has traditionally increased the efficiency of the network. Reconfigurable optical add/drop multiplexers (ROADMs) and mini-ROADMs have greatly contributed to this increased routing flexibility by enabling wavelength channels to be selectively added or dropped at any node in the network. However, ROADMs employ fairly complex and expensive components to provide this flexible routing capability along with resilience against fiber and node failures, meaning that ROAMDs prove cost-prohibitive in some contexts.
One such context relates to a network that efficiently transports the traffic of multiple services in a converged fashion. Rather than employing multiple different networks in parallel for transporting these different services (e.g., mobile, business, and residential services), a converged network transports those services together using the same network. A transport network that optically converges different services by transporting those services on different wavelength channels would be advantageous, for a variety of reasons, but has heretofore been precluded by the high cost of the necessary hardware components (e.g., ROADMs and mini-ROADMs).
Consequently, known transport networks converge different services using packet aggregation instead. While packet aggregation currently requires less hardware expense for converged transport, that expense will not scale equally with the significant traffic increases expected in the near future. Moreover, while packet aggregation suffices in many respects for realizing convergence, it proves inefficient in implementation. Indeed, converging multiple services at the packet level involves significant complexity in order to accommodate the different packet requirements associated with the different services.